1. Field of the Invention
The present invention relates to a bioelectrical impedance measuring apparatus equipped with a personal data input unit.
2. Prior Art
FIG. 8 shows a conventional body fat meter 200 equipped with a weight scale 200a (hereinafter, referred to as xe2x80x9cbody fat meterxe2x80x9d). The body fat meter 200 includes a bioelectrical impedance measuring apparatus as one component. At the outset it is necessary that user""s personal data such as adult or child, sex or height be inputted and stored in a memory preliminary to required measurements in the body fat meter 200. Entry of such personal data can be effected by using individual keys 201 to 204, which are allotted to individual users for their exclusive use. In measuring his weight and body fat percentage, the user depresses the selected individual key 201, 202, 204 or 204 by finger or tiptoe to retrieve the personal data from the memory, and then the user stands on the body fat meter 200 with his feet on electrodes A, B, C and D, which are arranged on the body fat meter 200, thus starting the required measurement.
Individual keys 201, 202, 203 or 204 to be depressed in inputting the personal data or in retrieving the same from the memory are mechanical devices which require application of significant strength of force for operation. This bothers the user more or less.
Such extra individual keys 201 to 204 are arranged on the body fat meter 200. Use of such extra parts increases the manufacturing cost accordingly, and the probability of malfunction in the body fat meter 200 caused by the frequent use of such mechanical devices.
When the body fat meter 200 is stood on the floor with its individual keys down after use, it is likely that the individual keys are pressed by the weight of the body fat meter 200, thereby vainly wasting the electric power from the battery.
In view of the above a bioelectrical impedance measuring apparatus comprising a personal data input unit which is used in inputting personal data and a plurality of electrodes which are used in measuring bioelectrical impedance is improved according to the present invention in that it comprises: a memory in which the personal data are stored via said personal data input unit; and a control device which carries out a required control by using at least one selected electrode to store the personal data in said memory or to retrieve the personal data from said memory. The electrodes take the role of said individual keys, thus eliminating the necessity of providing the apparatus with individual keys in the form of mechanical devices as in the conventional structure.
The bioelectrical impedance measuring apparatus may comprise further a power switch device responsive to a touch to any one of said electrodes for turning power on. This facilitates the operation of the apparatus.
The bioelectrical impedance measuring apparatus may comprise further a weight scale and a display, said control device being responsive to the inputting of a predetermined number in place of the height via said personal data input unit for permitting said weight scale to measure the weight alone and for permitting said display to show the so measured weight alone.
The bioelectrical impedance measuring apparatus may comprise: a bioelectrical impedance measuring circuit which measures the bioelectrical impedance appearing between selected points of a living body, on which points said electrodes are attached; a touch-sensitive switch circuit which is responsive to a touch to any one of said electrodes for making weak current flow through the touched electrode; and a mode switching device which switches the connection of said electrodes from said bioelectrical impedance measuring circuit to said touch-sensitive switch circuit or inversely.
The control device may include an internal timer for counting the length of time for which an interruption continues in the course of entry of the personal data or in the course of measurement; and the control device may be responsive to the length of time thus measured exceeding a predetermined length of time for making said electrodes to be connected to said touch-sensitive switch circuit via said mode switching device, and shutting power off.